内皮素对肾小球系膜细胞炎症效应的作用

Effects of endothelin on glomerular mesangial cells

本文从三个方面观察了内皮素-1(ET-1)对系膜细胞炎症效应的作用,结果表明:①可刺激系膜细胞收缩;②对系膜细胞合成DNA具有刺激作用,而且此作用具有剂量与时间依赖性;③可刺激系膜细胞分泌肿瘤坏死样因子。ET-1对系膜细胞的上述作用,提示它在肾炎发病中可能具有重要意义。

The newly discovered endothelium-derived peptide, endothelin (ET), has a potent contractile and mitogenic effects on vascular smooth muscle cells(VSMC). Glomerular mesangial cells(MC)share similarities in many ways with VSMC, so we designed this study to examine the inflammatory responses of cultured rat MC to ET-1. Firstly, the contractile action of MC to ET-1 was examined by phase contrast microscope. MC showed a marked contraction when they were incubated with ET-1 (10^(-9)M, 10^(-8)M and 10^(-7)M) for 30min. Secondly, the proliferation of MC after stimulation of ET-1 was evaluated with ~3H-thymidine incorporation. ET-1, incubating with MC for 24 h, led to MC proliferation in a dose-dependent manner with a threshold at 10^(-9) M. ET-1 also time-dependently resulted in MC proliferation when the ET-1 at 10^(-7) M incubated with MC more than 18h. Thirdly, the activity of tumor necrosis factor(TNF)released by MC in response to ET-1 was measured with L929 cell lyric assay. The TNF activity of MC was inn lower level without ET-1 stimulation, but significantly increased after incubation with ET-1 in a dose-dependent way(10^(-10)M, 10^(-9) M and 10^(-8)M). So, ET-1 can stimulate MC contraction, proliferation and release of TNF-like factor from MC in vitro, which may contribute to the development of glomerulonephritis in vivo.